Various curing devices and use of radiation curable coatings and devices or systems for use in collision and cosmetic repair of body parts of vehicles such as cars and trucks are known. Conventional devices and uses typically require a combination of radiation curable coatings, such as primers, a radiation source or radiator, and a power supply. For example, systems currently available from Cure-Tek® in 400 W and 1200 W systems are large, clumsy and difficult to maneuver in a congested repair shop. Typically the curing area is small in relation to these systems, and the irradiation output is typically about 100 milli-watts at a distance of about 10 inches. In this system the lamp is stationary while curing, and must be moved from place to place in order to cure relatively large surfaces such as vehicle body panels. Also, due to the round, or circular configuration of the reflector, insufficient irradiation intensity and non-uniform curing, a “light ring” defect results in some applications.
Also, while typically, an ultraviolet (UV) source such as a UV lamp can be used for curing a UV curable coating composition, such as a paint primer, applied over a substrate to form a cured coating layer; such UV radiation from the UV lamp can be harmful for operators during the use. This problem is in addition the aforementioned deficiencies of conventional irradiators, and their poor quality, inefficient and slow irradiation times that have plagued the collision and cosmetic repair of vehicles industry.
Typically, modern primers are polymeric in nature and are dried, or cured through use of a photo-initiator. UV radiation in the range of about 200-400 nm is typically used as a photo-initiator in this industry. Conventional irradiators used in this industry are not mobile, have irradiation sources that provide point or narrow radius concentration of curing irradiation, typically UVA, are clumsy to handle, and lack control and indication information that would be useful to an operator.
In the automotive repair industry, repair of cars and trucks often require painting or repainting of various surfaces, ranging from repainting of entire panels of body parts for the vehicle to repainting relatively small areas that have suffered dents, scratched, and the like. Typically, repair of vehicles includes preparing the surface to be painted or repainted, which typically includes coating the surface with a primer in the painting booth of a body shop in order to comply with OSHA and other governmental regulations. In these uses the slow and uneven curing provided by conventional irradiators are sources of problems. Specifically, because typical, slow conventional curing times, typically about 30 minutes results from use of conventional curing irradiators. These slow cure times create bottlenecks in high volume applications because the painting booth is then tied up while the primer cures and is not available to the operators for other tasks such as sanding the cured surface in preparation for actual painting.
With the novel UV mobile curing devices described herein, improved methods of curing irradiation curable coatings are made possible, particularly in the vehicle repair industry where car and truck panel surfaces and areas that have suffered nicks, scratches or other relatively small area damage require re-painting. The basics of UV curing technology are known, as shown for example on the Internet at http://www.cureuv.com/uv-lamp-curing-technology-101.html. For the purpose of the presently described devices and methods the terms WPI, intensity, dosage, wavelength, reflector, and cooling and photo initiator are intended to have the same meaning as defined in this Internet reference. With respect to the UV curing methods described herein, UV lamps used in these methods generally produce a spectrum of radiation as is known. As is also well known, industrial curing, the intended use of the described mobile irradiator and methods herein, is conducted primarily in the range of UV-C, UV-B and near UV-A, that is, from slightly below about 200 nm to slightly above about 400 nm. The peak intensity occurs at about 365 nm, with other smaller peaks at other wavelengths. The far ultraviolet lies between 200 nm and 300 nm, and is referred to as Germicidal or UV-C. The middle ultraviolet lies between 280 nm and 320 nm and is referred to as Erythmea (suntan) or UV-B. The near ultraviolet lies between 320 and 400 nm, and is commonly called Black Light (long ultraviolet) or UV-A. Therefore, needs exist for improved irradiation system for use in collision and cosmetic repair of vehicles that successfully address these known, long-felt needs.